THE LABYRINTH AND THE EIGHTH NERVE 391
introduction of the acoustic impedance meter provides a means of deter-
mining the presence or absence of an acoustic stapedius reflex. If this reflex
is absent the lesion is above the point of exit of the nerve to the stapedius
muscle, while if it remains present the lesion is below that level.
SYMPTOMS. Severe neuralgic pain in the ear precedes the herpetic eruption
on the auricle (Fig. 208), external auditory meatus and tympanic membrane,
which is commonly accompanied by facial paralysis of lower neurone type
and sometimes homolateral loss of taste of the anterior two-thirds of the
Fig. 208. Herpes zoster oticus.
tongue. Acoustic and vestibular complications are not infrequent, due to
extension of the inflammatory process to the adjacent eighth nerve and its
acoustic and vestibular ganglia. These vary from a slight diminution of
hearing to a severe form with tinnitus, deafness and vertigo with nausea,
vomiting and nystagmus. An increase of lymphocytes in the cerebrospinal
fluid has been observed. The acute features of the disease usually run a
rapid course, but resolution of the associated facial palsy may be slow,
while some hearing impairment may be permanent.
TREATMENT. Analgesics are called for and even morphine may be indicated.
The skin eruption should be kept dry. Suggestions regarding treatment have
included vitamin Bx and cortisone, while chloramphenicol has a specific
effect on some viruses. After the acute stage has subsided, massage, exer-
cises and electrotherapy may be given for the facial paralysis.
DEAFNESS DUE TO DRUGS
It is well known that quinine and the salicylates may cause deafness, which
is generally accompanied by tinnitus and sometimes by vertigo. In people